Snap hinge for furniture doors

ABSTRACT

Furniture hinge of a snap type holding the door open after a predetermined movement of the door in a door opening direction and exerting a closing force on the door as the door moves past a dead point toward its closed position. A socket member mortised in the door forms a stop for the door, a pivot support for two swing levers pivotally connected to a bracket member extending from a wall of the cabinet and hinging the door for movement about an imaginary axis. A spring formed integrally with the socket member extends outside of the socket member and is inclined at an oblique angle relative to the plane of the door. The spring has engagement with an end of the innermost swing lever within the socket and moves the door toward a closed position when moving past the dead position, upon door closing movement. The socket member and spring are preferably molded from a single piece of plastic material.

United States Patent Lautenschl'rieger, Jun. {451 Apr. 3, 1973 [54] SNAP HINGE FOR FURNITURE DOORS [57] ABSTRACT [75 l Assignee: Karl Lautenschl'zieger, Jun., Wer- "T sau/Odenwald, Germany Furniture hinge of a snap type holding the door open after a predetermined movement of the door in a door [73] Assigneez Karl Lautenschlaeger KG Rein opening direction and exerting a closing force on the heim/Odenwald, Germany door as the door moves past a dead point toward its W closed position. A socket member mortised in the [22] Ffled: 1971 door forms a stop for the door, a pivot support for two [2]] A l N 129,016 swing levers pivotally connected to a bracket member extending from a wall of the cabinet and hinging the door for movement about an ima inary axis. A s ring [30] Forelgn Apphcahon Pnomy Data formed integrally with the sock et member ex'zands Apr. 7, 1970 Germany ..P2016 398.8 outside of the socket member and is inclined at an oblique angle relative to the plane of the door. The [52] US. Cl ..l6/l63, 16/164 spring has engagement with an end of the innermost [51] Int. Cl. ..E05d 3/06 swing lever within the socket and moves the door [58] Field of Search ..16/ 163, 164, 165 toward a closed position when moving past the dead position, upon door closing movement. The socket [56] Re erences Cited member and spring are preferably molded from a sin- FOREIGN PATENTS OR APPLICATIONS 2,005,853 4/1969 France ..16/l64 Primary Examiner-James T. McCall Assistant Examiner-Doris L. Troutman Attorney-l-lill, Sherman, Meroni, Gross & Simpson gle piece of plastic material.

10 Claims, 5 Drawing Figures PATENTEBAPM ma 3. 72 4.021

Inven /01'.- A ar/ Laufensch/ager by Attgs.

SNAP HINGE FOR FURNITURE DOORS BACKGROUND, SUMMARY AND OBJECTS OF INVENTION Snap hinges biased by one or more springs to exert a closing force on the door have previously been known. Such hinges have required a separate spring or springs connected between the hinge and wall or door of a cabinet.

The hinge of the present invention improves upon the previous snap hinges in that it is supported in a socket member mortised in the door and has an integrally formed spring extending at an oblique angle with respect to the plane of the door toward the wall of the cabinet and facing the articulated joint between the door and wall of the cabinet. This spring extends out of the socket member and is slidably engaged by a cross piece of a swing lever for the door and biases the hinge lever and door toward a closed position after passing over a dead point of the swing lever and door and holds the door in this closed position.

The snap hinge shown and described therefor provides an integral socket member and spring inserted in a mortise in the door, in which the spring extends from a wall of the mortise toward the wall of the cabinet in a direction to exert a closing force on the door. The spring is adapted to be manufactured integrally with the socket member in an injection molding process.

The principal advantages of the snap hinge of the present invention are in the simplicity of the hinge enabling a dead point in door opening and closing directions to be located shortly before the door is in its fully closed position, and holding the door in this closed position until manually openagainst the spring and past the dead point of the door.

Another advantage of the present invention is that the spring and swing arm cooperating therewith have such a relationship with-respect to each other that the dead point position of the spring and door is only a fraction of the effective length of door opening movement.

A still further object of the invention is to improve upon the snap hinges heretofore used in furniture by supporting the door on the wall of a cabinet by a quadrilateral link structure in the form of two swinging levers, to move about an imaginary pivot and to so arrange the spring as to cooperate with one of the levers and exert a door closing force thereon, as it passes by a dead position in door closing movement of the door.

Other objects, features and advantages of the invention will be readily apparent from the following description of a certain preferred embodiment thereof, taken in conjunction with the accompanying drawings, although variations and modifications may be effected without departing from the spirit and scope of the novel concepts of the disclosure.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagrammatic horizontal sectional view showing a door hinged to a cabinet wall according to the principles of the present invention, with the door in a partially open position.

FIG. 2 illustrates the hinge and door shown in FIG. 1 in a closed position.

FIG. 3 is a plan view of the socket member with the swing levers and bracket members supporting the door on the cabinet wall removed.

FIG. 4 is a fragmentary cross sectional view taken through the spring along line IV-IV of FIG. 1; and

FIG. 5 is a schematic view illustrating the positions of the swing lever and spring in the dead position of the spring and hinge and in the closed position of the door.

DESCRIPTION OF PREFERRED EMBODIMENT OF INVENTION In the embodiment of the invention illustrated in the drawings, I have shown in FIGS. 1 and 2 a door 1 hinged to a wall 2, which may be the wall of the cabinet, by a hinge constructed in accordance with the principles of the present invention. The hinge is shown as including a socket member 3, which may form a stop for the door and forms a pivotal mounting for a pair of swing levers 6 and 7. The socket member 3 is shown as mortised in a recess or mortise 3a extending into the door from the inside thereof, and having a wall perpendicular to the plane of the door.

The socket member 3 is generally circular in plan view and has a fastening flange 4 extending from one side thereof along the inner face of the door, and suitably secured thereto in spaced relation with respect to the mortise 3a. Screws or other suitable securing means (not shown) may be provided to secure the fastener flange 4 and socket member 3 to the door.

The cabinet wall 2 has a carrying arm 5 extending along the inside thereof toward the socket member 3. The carrying arm 5 has a bracket arm 5a extending therefrom beyond the inside and end of the door into the interior portion of the socket member 3, and forming a mounting for an end of the swing lever 6 on a pivot pin 1 l. The opposite end of the swing arm 6 from the pivot pin 11 is pivoted to one side of a tongue 6a on a pivot pin 17. The tongue 6a is shown as extending inwardly from the interior wall of the socket member 3 in a generally radial direction. The swing arm 7 is also pivoted to the bracket or tongue 6a on a pivot pin 7a, spaced from the pivot pin 17 toward the plane of the inside surface of the door and disposed radially out wardly of the pivot pin 17. The swing arm 7 is pivoted at its opposite end to the bracket arm 5a on a pivot pin 7b. While the swing arms 6 and 7 are shown as being pivoted to-one side only of the tongue 6a, it should be understood that said swing arms may be pivoted to opposite sides of said tongue and to opposite sides of the arm 5a where required. The swing arms 6 and 7 thus provide a quadrilateral hinge support for the door 1, supporting the door for movement into open and closed positions about an imaginary axis and accommodating full opening and closing of the door.

I have shown in FIGS. 1 and 2 the socket member 3 as having a spring 9 extending from the bottom thereof on the outside of the pivot pin 11 and swing arm 6 and inclined with respect to the wall of the mortise 3a toward the cabinet wall 2 at an oblique angle with respect to the inner face of the cabinet door. The side of the spring 9 facing the cabinet wall 2 is slidably engaged by an eye 10 of the swing arm 60 pivotally mounting said swing arm to the pivot pin 11. The eye 10 may have a lateral extension thereon (not shown) providing a relatively wide bearing surface slidably engaging the spring 9.

The spring 9 may be formed integrally with the .socket 3 by slitting the molded socket member to cut out sections 8 on opposite sides of said spring to accommodate free retractable movement of said spring during door opening movement of the hinge beyond a predetermined dead point, and then to accommodate the spring 9 to hold the door in an open position. In a contrary manner, as the eye 10 reaches the dead point of the hinge and swing arm 6, the spring engaging the eye 10 will bias the door into a closed position and securely hold it in this position.

The end of the spring 9, spaced inwardly of the plane of the door, has a spring 12 connected thereto and formed from the fastening flange 4 by slitting along said flange along cut out lines 13, 13 on opposite sides of said tongue. The spring 12 is thus of a curved form and is arched upwardly relative to the plate of the inner surface of the door along an arc, although it need not necessarily be formed along an arcuate configuration. The springs 9 and 12 may be integrally formed from a suitable plastic material molded by injection molding and cutting the slits 8 for the spring 9 and the aligned slits 13 for the spring 12. It should here be understood that the springs 9 and 12 need not be integrally formed with each other, or with the socket member 3 but may be separate metal springs of various conventional forms arranged to perform the function of the springs 9 and 12. The space between the door surface and the spring 12 may be closed by closure pieces 14, 14 extending upwardly along opposite sides of the spring 12 and illustrated in plan in FIG. 3.

The cross section of the spring 9 in FIG. 4 shows said spring as generally channel-like in form and having a series of parallel grooves 15 extending longitudinally therealong, which can be used for the reception of a lubricant. A longitudinal stiffening rib 16 extends along the opposite side of the spring 9 from the grooves 15 and converges at its lower end to the plane of said spring to restrict deformation of the upper end portion of the spring, and accommodate a major portion of deformation of the spring in a zone adjacent the bottom portion of the spring.

In FIG. 5 of the drawings, I have diagrammatically illustrated the deformation of the springs 9 and 12 and illustrated the biasing of the swing arm 6 toward a door closing position, as the pivot pin 11 for said swing arm passes the dead point of the spring 9.

In this Figure, the swing arm is shown in a closed position by solid lines, with the dead point indicated by a dot and dash line at an angle alpha from a center line extending through the centers of the pins 17 and 11 when the door is in a closed position and indicated by a dot and dash line.

The point of maximum deflection of the spring 9 at the dead point of the spring and swing arm 6 from the rest position of the spring is indicated by dot and dash lines and amounts to the angle gamma, and is substantially As the door moves toward the closed position, the spring 9 does not recede to the full angle of 20, but by an angle beta equal to substantially 17. The spring 9, therefore, is partially flexed or under tension in the closed position of the door. This residual spring tension in the closed position of the door exerts a force holding the door closed.

Now comparing the length of the lever arm of the spring 9 which is active in the closing position of the door and extends from a pivot axis 18 to the line of contact with the eye 10, with the length of the lever arm extending from the contact line to the entry line 19, the length of the first lever arm is only a fraction'of that of the secondwith the result that the holding force of the spring 9 is increased over the force exerted by the spring.

Where the spring 12 is formed integrally with or connected with the spring 9, the spring force may be materially increased for larger doors and spring hinges.

It should be understood that while I have shown two swing arms 6 and 7, that the door in many cases can be supported on one swing arm and that the swing arm 6 will then form a support for the door and be slidably supported on the upper surface of the tongue 6a. Where the tongue 6a and socket member 3 may be made from metal, rollers or other antifriction means may be used to reduce friction. Such rollers, however, are not necessary with plastics, particularly those plastics which come under the collective term acetal resins, which have the requisite mechanical strength, and elastic resilience to take the continuous stress on the hinge in practical use of the hinge.

I claim as my invention:

1. A snap hinge particularly adapted for furniture doors and in combination with two members, one of which is relatively movable with respect to the other, to.

effect a closure of the door opening,

a socket member mortised in one member,

a carrying arm secured to the other of said members and having a portion extending over said socket member when said members are in an open position,

at least one swing arm transversely pivoted to said socket member within the margins thereof,

means connecting the opposite end of said swing arm to said carrying member and movable to extend along said socket member when said relatively movable members are in their closed position at right angles with respect to each other,

said socket member having a continuous generally cylindrical outer wall,

a spring tongue cut from said outer wall and extending angularly inwardly of said socket member from the bottom thereof and having an integral yieldable pivot adjacent the bottom of said socket member,

said spring tongue providing an angular contact surface contacted by said swing arm adjacent the yieldable pivot of said spring tongue, when said relatively movable members are in a closed position and movable along said spring tongue as said relatively movable members move toward an open position, and biasing said swing arm and carrying arm in a closing direction and retaining said rela tively movable members in closed positions by the bias of said spring tongue,

the socket member and spring. tongue being integrally formed from a plastic material and the bias of said spring tongue being attained by the angular position of said tongue and the plastic material from which it is made.

2. The snap hinge ofclaim 1,

wherein two of said swing arms are provided, and

wherein the two swing arms form a connected rectangular parallel axis swing joint between the connections of said swing arms to said socket member and said carrying arm.

3. The snap hinge of claim 2,

wherein the spring tongue has a dead position and is effective to exert a biasing force to hold the relatively movable member open when said swing arm slidably engaging said spring tongue is on one side of said dead position and to bias the relatively movable members into a closed position when said swing arm is on the opposite side of said dead position, and

wherein the dead position is at an angle of from 5 to l0 from the fully closed position of said two relatively movable members.

4. The snap hinge of claim 3,

wherein the spring tongue is deflected from its rest position at approximately in the dead point position and in the closed position at approximately 3.

5. The snap hinge of claim 3,

wherein said socket member has an elongated mounting flange extending therefrom in alignment with said spring tongue,

and wherein said mounting flange has an upwardly arched leaf spring extending therealong and connected at its free end to the free end of said spring tongue.

6. The snap hinge of claim 5,

wherein the upwardly arched spring and spring tongue are integrally formed and formed integrally with said socket member and said mounting flange.

7. The snap hinge of claim 5,

wherein the surface of said spring tongue engageable with the innermost of said swing arms has a series of longitudinal grooves extending therealong for a lubricating agent.

8. The snap hinge of claim 4,

wherein the spring tongue has at least one stiffening rib extending along its outer side.

9. The snap hinge of claim 4,

wherein the socket member, bracket arm, spring tongue and arched spring are made from an acetal resin plastic material.

10. The snap hinge of claim 5,

wherein the spring tongue extends beyond the plane of the member on which it is mounted and the leaf spring is integral with the mounting flange and the spring tongue and is in the form of an arcuate leaf spring arched from the plane of the member on which it is mounted when the relatively movable members are in a closed position. 

1. A snap hinge particularly adapted for furniture doors and in combination with two members, one of which is relatively movable with respect to the other, to effect a closure of the door opening, a socket member mortised in one member, a carrying arm secured to the other of said members and having a portion extending over said socket member when said members are in an open position, at least one swing arm transversely pivoted to said socket member within the margins thereof, means connecting the opposite end of said swing arm to said carrying member and movable to extend along said socket member when said relatively movable members are in their closed position at right angles with respect to each other, said socket member having a continuous generally cylindrical outer wall, a spring tongue cut from said outer wall and extending angularly inwardly of said socket member from the bottom thereof and having an integral yieldable pivot adjacent the bottom of said socket member, said spring tongue providing an angular contact surface contacted by said swing arm adjacent the yieldable pivot of said spring tongue, when said relatively movable members are in a closed position and movable along said spring tongue as said relatively movable members move toward an open position, and biasing said swing arm and carrying arm in a closing direction and retaining said relatively movable members in closed positions by the bias of said spring tongue, the socket member and spring tongue being integrally formed from a plastic material and the bias of said spring tongue being attained by the angular position of said tongue and the plastic material from which it is made.
 2. The snap hinge of claim 1, wherein two of said swing arms are provided, and wherein the two swing arms form a connected rectangular parallel axis swing joint between the connections of said swing arms to said socket member and said carrying arm.
 3. The snap hinge of claim 2, wherein the spring tongue has a dead position and is effective to exert a biasing force to hold the relatively movable member open when said swing arm slidably engaging said spring tongue is on one side of said dead position and to bias the relatively movable members into a closed position when said swing arm is on the opposite side of said dead position, and wherein the dead position is at an angle of from 5* to 10* from the fully closed position of said two relatively movable members.
 4. The snap hinge of claim 3, wherein the spring tongue is deflected from its rest position at approximately 20* in the dead point position and in the closed position at approximately 3*.
 5. The snap hinge of claim 3, wherein said socket member has an elongated mounting flange extending therefrom in alignment with said spring tongue, and wherein said mounting flange has an upwardly arched leaf spring extending therealong and connected at its free end to the free end of said spring tongue.
 6. The snap hinge of claim 5, wherein the upwardly arched spring and spring tongue are integrally formed and formed integrally with said socket member and said mounting flange.
 7. The snap hinge of claim 5, wherein the surface of said spring tongue engageable with the innermost of said swing arms has a series of longitudinal grooves extending therealong for a lubricating agent.
 8. The snap hinge of claim 4, wherein the spring tongue has at least one stiffening rib extenDing along its outer side.
 9. The snap hinge of claim 4, wherein the socket member, bracket arm, spring tongue and arched spring are made from an acetal resin plastic material.
 10. The snap hinge of claim 5, wherein the spring tongue extends beyond the plane of the member on which it is mounted and the leaf spring is integral with the mounting flange and the spring tongue and is in the form of an arcuate leaf spring arched from the plane of the member on which it is mounted when the relatively movable members are in a closed position. 